Lock protected filling cap for liquid fuel tanks



Dec. 1, 1942. s. wxs: 2,303,594 Loox PRoTEcTED FILLING CAPs lPoR LIQUIDFUEL TANKS Filed Haren 11, 1940 -2 sheejns-sneet 1 n .In al Dec. 1,1942. s. wiss 4 ZI''M LOCK PROTEOTED FILLING QAPS FOR LIQID FUEL TA-NXSFiled uarcn 11, 1940 2 siens-sheet 2 *INVENTOR o/om or? H//Se' PatentedDec. 1, 1942 UNITED STATES LOCK PROTECTED FILLING CAP FOR. LIQUID FUELTANKS Solomon Wise, Cleveland, Ohio Application March 11, 1940, SerialNo. 323,291

11 Claims. l(Cl. 'l0-165) yThis invention relates to filling caps forgasoline or like liquid fuel tanks, such for example as those providedon automotive vehicles, and to such caps. having key-operated locks toprevent their unauthorized removal.

As is well known, the gas or other liquid fuel tank of anautomotivevehicle or the like is filled through a tube or stem, which isthereafter closed by a detachable cap to keep out dust and other foreignmaterial and to seal the tankto prevent escape or evaporation of thefuel, the cap being constructed to bleed air into the tank to maintainit at atmospheric pressure to facilitate feeding of the fuel to theengine.

It has been proposed' to provide such filling caps with key-operatedlocks to prevent their unauthorized removal, one purpose being toprevent the theft of the liquid fuel.

The lock protected cap of the present invention embodies improvementsover prior caps of this general class as will be explained hereinafter.

It is among the objects of the present invention:

To provide an improved filling cap of the class referred to which may beattached to and detached from the lling stem of a tank by rotating itthereon, and which, after it has been rotated to attach it, may belocked by a keyoperated lock, and thereby the outer accessible parts ofthe cap are freed, so that if rotated, they rotate freely withoutdetaching the cap;

To provide an improved tank filling cap of the lock-protected type,provided with a removable key to lock it, the key hole `of which iscovered or uncovered by a dust cap which is selfcentering to hold it inkeyhole uncovering or keyhole covering position in an improved manner,and which dust cap on being moved from keyhole covering positionautomatically moves away from the parts surrounding the keyhole wherebyit is prevented from adhering thereto by frost, dirt, etc.;

To provide a lling cap of the lock protected type, having a key operatedlock the key of which cannot be removed except when it is in theposition to lock the cap against removal;

To provide a filling cap mechanism of the lock protected type, having akey operated lock the key of which is interlocked with the parts of ther mechanism when in unlocked position, so that it cannot be removedexcept when it is has been operated to lock the cap;

.To provide an `improved means for assembling the parts of alock-protected filling cap, and an 55 improved construction of the partsthereof to facilitate the said method of assembling;

To provide an improved arrangement of parts of a lock protected fillingcap mechanism and an improved means of assembling said part-s wherebysaid mechanism parts may be made from die cast metal without thenecessity of removing the parting line n formed thereon by thediecasting process;

To provide an improved filling cap of the lock protected class havingouter accessible cap parts which are freely rotatable when locked, andwhich may be key operated to set a lock mechanism which will audiblysnap into one of a plurality of unlocked positions upon subsequentrotary movement of the outer cap parts to render the cap removable uponrotation of the outer accessible parts;

To provide a filling cap having an outerpart which is freely rotatablewhen locked and provided With a locking tongue arranged to registerWithva plurality of locking teeth and which may be moved into positiontol engage the teeth Whether it is in registration therewith or not;

To provide a filling cap having a freely rotatable outer part, which maybe unlocked by a locking tongue upon movement thereof into position to be engaged with one of a plurality of locking teeth upon rotation of theouter cap part, by means of a spring element which spring element alsofunctions to prevent loose rattling of the tongue;

To provide a filling cap having an improved means of the bayonet jointtype for engaging it with the filling stem of a tank, and provided withimproved resilient means of the follow-up type for maintaining theengagement, and provided with improved means for preventing yielding ofthe resilient means beyond a predetermined degree;

To provide a filling cap of the rotary cover lock protected typeprovided with an improved inlet for air to the tank disposed to preventthe entrance of excess moisture through the mechanism of the lock andinto the tank to which the cap is attached.

Other objects will be apparent to those skilled in the art to which myinvention appertains.

Myinvention is fully disclosed in the following description taken inconnection with the accompanying drawings, in which;

Fig. 1 is a top plan view of a filling cap embodying my invention andillustrating in broken line diiferent positions which a key-hole coverthereof may assume;

Fig. 2 is a longitudinal sectional view taken from the plane 2-2 of Fig.l, and illustrating the filling cap embodying my invention mounted uponthe filling stem of a tank and with the parts in locked position, thatis to say, with the outer enclosing portions of the cap freely-rotatableto thereby prevent removal of the cap;

. Fig. 3 is a bottom plan View of the parts lof Fig. 2 but with thelling stem of that figure omitted;

Fig. 4 is a sectional view taken from the plane 4--4 of Fig. 2 and withthe said filling stem omitted;

Fig. 5 is a sectional view taken from the plane 5-5 of Fig. 2;

Fig. 6 is a view similar to Fig. 2 but illustrating the parts thereof inthe position which they assume when the outer covering part of the capis in the unlocked position whereby upon rotating the outer coveringpart the cap as a whole may be rotated to remove it from the fillingstem; this view illustrating the operation of the locking parts when atongue thereof happens to be out of alignment with tooth spacesco-operating therewith;

Fig. 'l is a view taken from the plane 'I-'I of Fig. 6; u

Fig. 8 is a fragmentary view similar to a part of Fig. 7 but showing thelocking tongue after it has been rotated with the outer covering part tosnap into a co-operating tooth space;

Fig. 9 is a fragmentary view similar to Fig. l but with the keyholecovering cap of that figure removed and with a key in the key hole; andillustrating the means by which the key maybe locked against removal inthe unlocked position;

Fig. 10 is a fragmentary View taken from the plane Ill-I8 of Fig. 9;

Fig. l1 is a view which considered with Fig. 9, illustrates theconstruction by which the keyhole covering cap is caused tomove axiallyaway from the key-hole when rotated to uncover the keyhole;

Fig. 12 is a fragmentary view of anfenlarged scale of a part of Fig. 2illustrating a preferred step of assembling certain parts which I mayemploy. l

As will become apparent hereinafter, the lling cap embodying myinvention, and as illustrated in the drawing, comprises in general twoparts, an attaching part and an outer accessible or covering part. Thesetwo parts are arranged to be connected together by a key-operatedlocking mechanism so that by rotating the outer part, the attaching partrotates therewith and may be secured to, or removed from the fillingstem of a tank by the usual bayonet type attachment. When the lock isoperated by a key to disconnect the two parts, the outer part may befreely rotated on the attaching part, whereby it is impossible to supplysuflicient torque to the attaching part to detach it from the stem,thereby preventing unauthorized access to the tank through the stern. Itfollows that when the two parts are locked together, the cap as a wholecan be removed, and when they are unlocked from each other, they cannotbe removed, but as a matter of terminology, it is the locked conditionof the parts which prevents removal of the cap and the unlocked positionof the parts which permits the cap to bev removed, and this use of thewords locked and unlocked will be adhered to in the following, and hasbeen so used hereinbefore.

Referring to the drawing, Fig. 1, I have shown at I the sheet metal stemcustomarily attached to a fuel tank by a flange 2 the upper end of thestem being rounded over as at 3 to provide a smooth annular end surfaceupon which a sealing gasket 4 may be pressed, and the sheet metal beingrolled or pressed inwardly as at 5 5. The rolled-in portion 5 is is wellknown in such stems co-operates with the usual standard equipment caphaving a T-head extending,

therefrom, the portion 5 having opposite notches downwardly throughwhich the T may be projected and having cam surfaces over which theopposite arms of the T may be forced to draw the cap toward the stem,and compress a gasket such as the gasket 4 upon the end of the stem at 3to seal it, the joint as thus commonly employed being in the nature of abayonet joint and being so well known in this art as not to need furtherdescription or illustration herein.

At 6 is illustrated generally the attaching part of my improved cap,.andat 1 is illustrated generally the outer or covering part thereof. Theattaching part 6 has a transverse planar face 8 engaging the annulargasket 4 and a cylindrical portion 9 centering the gasket thereon, 'thecylinder being closed by an end I0 provided centrally with a spring andlock housing I I, the housing II being internally cylindrical andprojecting externally downwardly from the closed end I0.

A sheet metal spring I2, best shown in Figs. 2 and 3, generally ofcircular form and provided with oppositely extending fingers I3--I3 ofdownwardly open channel form, has a central perforation by which it istelescoped over the downwardly projecting housing II, and is attachedintermediately of the fingers I3-I3 to the bottom I0 by rivets I4-I4. Inthe preferred construction, a spring guard I5 is provided having wingsIS-IS through which the rivets I4 pass, whereby the spring I2 is securedagainst the bottom I 0 by the wings I6-I 6, and the guard I5 is providedwith upwardly open channel form arms II--II, the other ends of which arenested in the downwardly open channel form fingers I3 of the spring.

By this means, when the attaching part 6 of the cap is attached to thestem I by inserting the spring fingers I3-I3 into the upper end of thestem, and rotating it to draw the part 6 downwardly to clamp the gasket'4 between the face 8 and the stem surface 3, the spring I2 is bentdownwardly at the fingers I 3 -I 3 but is prevented from being distortedbeyond its elastic linut by the fingers I'I-I'I upon which the springfingers I 3-I3 abut; but the resiliency is maintained in the spring I 2so that if the gasket II should become set or yield,the spring l2 bytending to assume its original straight position will maintain a seal atthe gasket nevertheless.

As shown in Figs. 2 and 6, the attaching 'part 6 of the cap is generallyof upwardly open cup form. The covering part 'I is, as is also shown inthese figures, of downwardly open cup form having la skirtV I8 extendingdownwardly and around the inner parts of the cap structure to protectand guard the same against tampering; and the two parts of the cap arejoined together in a manner to permit relatively rotary movement of theone on the other, by the following means, best shown in Figs. 2 and 12.The attaching part 6 has formed thereon an outwardly extending annularflange I9, and an annular cylindrical shoulder 20. The covering part Ihas a planar face 2| and an annular hollow cylindrical shoulder 22co-operating with'the flange I9 and shoulder 20,v to guide rotaryImovement4 of the covering part 1, and the attaching par-t` B, andv theseparts are held in co-operative position by an assembling ring 23. Thisring,. in the form ofa shallow dish, has a skirt 24 at its peripheryWhich at the time of assembling the parts is disposed in a groove 25 inthe covering part1, and the body of the ring 23 overlaps under the angeI 9 and engages an annular bead 26-on the covering part 1. The coveringpart 1v is formed from metal having a desired degree of ductility, and Ihave found that suitable die-casting alloys may be used for thispurpose; and when the part 1 is first formed, it has an annular rib 21formed thereon and disposed to permitthe ring 23 to be moved to itsposition illustrated in Fig. 12, describeda-bove, and then the r-ibA 21is bent inwardly to the position shown at 21A, clamping the skirt 24 ofthe ring 23 inthe groove 25 and against the bead 26, rigidly securing itto the covering part 1 and disposing Athe body ofthe ring to trap theflange I9 between the ring 22 and the bead 26, and with the shoulders 20and 22 adjacent, thereby providing a permanent rotary coupling betweenthe vattaching part and the covering part 1.

The attaching part E is preferably formed from die castmetal and in thisprocess aY casting fin may form on the outer peripheral edges of theflange I9 and I have found that the necessity of removing such fins maybe avoided if a space 28 is provided at the periphery of the flange I9!as shown in Fig, 12.

The rib 21 may be bent to the positionV 21A by a spinning or otheroperation, but I prefer to bend orforce it in position to grip the ring23 by a die-pressing operation, relative movement between the coveringpart 1 and the die being effected axially of the covering part 1, anddie pressing operations of this type being well'known it is not thoughtnecessary to further illustrate or describe the same.

As stated above, locking meansis provided to lock the two parts 9 and 1together whereby when torque is manually applied to the covering part 1to rotate it, it will rotate the attaching part 6 either to'attach it tothe stem I or to detach it therefrom depending upon the direction inwhich the covering part is turned; and after the attaching part isfastened to the stem I', the covering part 1 may be unlocked from theattaching part and therefore will rotate freely when torque is appliedthereto so that the torque is not transmitted tol the attaching part 6AandY therefore it cannot be removed. The rotary coupling connectionbetween the two parts has been described in connection with Figs. 2 and12, and the said locking means will now be described.

The attaching part 6 is provided internally thereof with an annularseries of spaced apart lock teeth or jaws 29-29,` eight being shown, seeFigs. 4, 7 and 8, although any suitable or desired number may beprovided.

A pair of guide posts 3I-3I depend from the covering part, Figs. 4, 5,6, and, transversely therefrom, a pair of posts 32-32 also depend fromthe covering part 1, and these pairs-of posts function to position andguide a lock reciprocator 33, having at opposite ends thereofV alignediingers 34 and 35, the finger 34 being disposed between and guided bythe posts 35-36. and the nger 35 disposed and guided'by the posts 32-32.

'Ihe intermediate portion ofthe reciprocator 33-is in the form of arectangular body, as shown in Figs. 4 and 7, and the reciprocatorymoveinV each direction ofi' reciprocaticn byv engage'.-

ment of this rectangle inone direction with the. posts3I and intheotherdirectionwith thepostsz 32, as shownrespectivelyf in Figs. 4 and 7; and.the reciprocator has a rectangular perforation. 36 therein.

A coiled spring' 31` is seated inv a recess,` inthe covering part 1, andatits-outer endpressesupon the upper. side-of' the' reciprocator 331resiliently holding it downwardly, andthus prevents rattling.4 thereof.and also performs asnap actionLtob'e referred to.

When the covering part 1 and attaching part 6 are in theirlockedpositionsttl'ie reciprocator 33 is in the retracted position ofFigs. 2 and; 4. To interlock the two parts together, that is"un: lockthe device, the reciprocator isreciprocated toward thel right, as viewedin the drawing, to

the position of Fig. 8, or in the position'` of Figs. 6 and '7. If. whenthe reciprocator is thusreciprocated,v the. nger 35. should, as shown:in Fig. 8, be thereby projected'into the space;be tween anadjacent pairof lockV teeth 29; the, interengagement of. the finger with the teeth'effects the interlock between the two parts 'prohibiting their relativerotation. If, however.; at the time of reciprocating the reciprocator`as above referred to, one of the teeth 29 should happen to be inalignment with the finger 35, the. finger Will ride up on the inclinedface 39 of. saidltooth, taking up the positiontliereofl in Figs; 6.'and.-'7.` Inasmuch as the locking operation is performed topermitdetachment of the cap from the'stem,

the covering part 'IY will now be turnedby hand to detach.the. capasa-whole and this turning motion will first cause' the coveringpart11'to start to turn onV the'v attaching partG, but such movementwill'move the finger 35` withth'er covering part and after. a. smallamount of movement, the finger 35 will snapdown into the space betweenthe next adjacent pair of teeth 29 and the two parts 6 and 1 will thenbe locked'together.. This positive snap action emits'an audible clickand is one of the advantages of my invention, .as well as isV theconcurrent advantage; of being able to move the reciprocator 33 to thelocking positionwhether or not'v thefinger 35 happens to be aligned withone. of the spaces between the teeth 29. Obviously itis the spring 31which effects this snap action.

Ihe means for` reciprocating the reciprocator 33 willnow be described.

In a cylindrical recess 38'in the coveringk part 1 of the cap isrotatably disposeda cylindrical lock head 39, Figs. 2, 5, 6 land 10,and' eccentricallyA with respect to the axis of rotation of the head 39Vis an upper lock. cylinder or skirt 49 formed onthehead 39'and1depending below the same. This hollow cylindrical skirt 49 extendsdownwardly into close proximity with the upper end of thecylindricalhousing II above referredA to and extends into the rectangularperforation 36 in the reciprocator 38. A dat sheet metal key 4Iisprovided which may be inserted through a key slot 42, Figs. 2 and10into the upper end' of the head 39, and Whenthe key is then turned itwill rotate the lock head 39 on itsaxis causing the skirt lI to movewith an eccentric move- -ment, for example from the position of Fig. 4

mentof the .reciprocator'3'3is limitedzandstopped':

the locked position of Fig. 2 for example, joverlap both the skirt 40and the vhousing II and prevent rotation of the lock head 39; but whichas shown in Fig. 6, may be moved by insertion of the key 4| to disposethe ends of the cylinders in a plane common to the adjacent ends of theskirt 4U and housing II whereby the key 4| may be turned for thepurposes described above.

The lock parts which I prefer to use do'not in themselves constitue anyessential part of the present invention, the same being the subject ofmy Patent No. 1,741,390, issued Dec. 21, 1929, for Improvements inlocks, except in so far as they make possible the use of a symmetricalselfejecting key, as will be described.

In order that the key 4I may be prevented from removal except when theparts are in the locked position, the following means is provided. Asshown above, when the key is inserted into the skirt 40 at its upper.end through the key slot 42, and is depressed to move the said lockingcylinders to their unlocking positions, the application of rotary torqueto the key 4| will rotate the lock head 39 and cause the key itself tomove bodily with the skirt, 40 with an eccentric movement around theaxis of the lock head 39, and the key moving bodily from the broken lineposition to the solid line position, Fig. 9, and I utilize this bodilymovement in the following manner.

The key is provided with a perforation 43 therein, Figs. and 6. 'I'heupper surface of the covering part 1 is provided with a sector-formopening 44 through which the key sweeps bodily; and a tongue 45 ofarcuate form is disposed in the opening 44 over which the perforation 43telescopes when the key is turned. The tongue thus interlocks the keywithv the covering part 1 when the key is turned to the unlockingposition and the key cannot be removed until it is turned again to thelocking position.

By this means, when the key interlocks the parts together so that thecap may be removed from the stem, the operator of the device, whether itbe the owner of the vehicle or the station attendant, cannotinadvertently remove the key with the danger that the cap will then beput on without locking it; and the key may be attached to the ignitionkey of the vehicle to further this purpose. I

Itis only after the cap has been again attached to the stem and lockedthat the key can be withdrawn, and this leaves the cap in the conditionso that the covering part rotates freely and the cap cannot be removed.

By utilizing the above described lockfcylinder type of lock, asymmetrical key may be used, and the perforation 43 will be on its axisof symmetry, so that the perforation will telescope over the tongue 45in every case. Furthermore, the lock-cylinder type of lock employedutilizes springs 53 and 54 in the housing |I tending at all times tohold the lock cylinders outwardly toward the upper end of the skirt 40;and since these springs must be compressed by insertion of the key 4| tomove the cylinders from the position of Fig. 2 to that of Fig. 6 in theoperation of the lock, these springs also function to eject the key 4|when it is returned to locking position, the broken line position ofFig. 9.

The key opening 44 and the key slot 42 are covered by a cover cap 46having the following construction.

The upper outer surface of the covering part 'I is provided with anupwardly concave V-notch 41 and the underside of the'cap 45 is providedwth a downwardly convex V-bead 48 alignable and nestable therewith. Apin 52 having a head 49 is projected upwardly through a perforation 50in the covering part with a spring 5|, between the head 49 and theperipheral portions of the perforation 50, tending to hold the pin 52downwardly; and the upper end portion of the pin is pressed into the cap46 at a point in the apex of the V-shaped bead 48.

The pin 52 thus provides an axle upon which the cap 46 may rotate, andbeing disposed at one side of the center of the cap and laterally of thesaid key-opening, the cap can be rotated laterally to cover or uncoverthe said opening.

When the cap is in the closed position, it is centered thereat by thenesting of the bead 48 in the groove 41, and when torque is applied toit to rotate it to the open position illustrated in Fig. 11, the bead 48rises up out of the groove 41 by a camming action and therefore elevatesthe cap above the covering part 1 of the cap. The cap thus has an axialmovement when rotated and by this means when rotating it from the closedposition to the open position is moved away from the underlying partsand therefore breaks away if it tends to stick, for example by frost.When moved to the closed position it is self-centering, the bead 48snapping into the groove 41 and the bead 48 and groove 41 may beproportioned so that the bead will not bottom in the groove but willpermit the peripheral or main portion of the cap to firmly engage theunderlying parts, for example at 51, Fig. 2.

At 55, Figs. 2 and 3, I have shown a vent hole communicating with theinterior of the tank through the stem and access may be had thereto, forinspection, through a large perforation 56 in the spring guard I5; andthe vent hole 55 communicates with the outside atmosphere through thehousing II, to the interior of the attaching part 6 and through therotary coupling at I 9, 28, 23 and downwardly under and through theskirt I8.

This communication between the tank interior and the outside atmospheremaintains the tank at atmospheric pressure, as fuel is Withdrawntherefrom, and the said pathfof communication through the rotarycoupling is of relatively great cross-sectional area and therefore ofrelatively small resistance to air flow inwardly therethrough; and theentrance of air through such path being upward, under the covered skirtI8, moisture even during a heavy rain, or snow cannot enter; and theonly other path of entrance, namely through the keyhole 42, is closedand sealed by the cap 46; thus the accumulation of water in the tank isprevented.

My invention is not limited to the exact details of constructionillustrated and described. Changes and modifications may be made withinthe spirit of my invention without sacrificing its advantages and withinthe scope of the appended claims.

I claim:

1. In a cap device for closing the lling opening of a tank or the like,an attaching part comprising means for attaching it to the tank and acovering part freely rotatably coupled to the attaching part; a lockmechanism operable by a key to lock the two parts together; the coveringpart comprising depending skirt portions surrounding and covering theattaching part; and

coupling means permanently rotatably coupling4 e. @acca-co4 the; partstogether, said-.coupling means compris- .ing coaxial-annular surfacesassociated-with 4said partsrespectively-and in mutual engagement, and`comprising integral portionsofone of fsaid parts forcibly deformedYtpermanently main-. tainsaidengagement.

2. In a device for closing the filling opening of a tank or the like, anattaching part comprising means for attaching it to the tank and acovering part freely rotatably coupled to the attaching part; a lockmechanism operable by a key to lock the two parts together comprising anelement rotatable on an axis by rotation of the key; and means toprevent removal of the key except when the two parts are unlocked fromeach other comprising a perforation provided in the key and a circularlyarcuate tongue on the covering part concentric with the said axisdisposed to enter the perforation when the key rotates the rotatableelement to the locking position.

3. In a cap device for closing the filling opening of a tank or thelikel an .attaching part comprising means for attaching it to the tankand a covering part freely rotatably coupled to the attaching part; alock mechanism operable by a key to lock the two parts togethercomprising a reciprocator on one said part and a circular series ofspaced teeth on the other said part each having an upwardly inclinedface; means responsive to turning of the key to cause the reciprocatorto ride up on theinclined face of a tooth when disposed in alignmentwith the reciprocator; and spring means resisting riding-up movement ofthe reciprocator; whereby when the covering part is rotated on the saidcoupling the reciprocator is caused by the `spring to snap into thespace between a pair of adjacent teeth to lock the covering part to theattaching part.

4. In a cap device for closing the filling opening of `a tank or thelike, an attaching part comprising means to attach it to the tank, and acovering part; a rotatable connection between the two parts comprisingmutually engaged annular portions; a ring for maintaining the saidportions in mutually engaged relation; and a projection on one said partbent to permanently overlap the ring and hold it in said maintainingposition.

5. In a cap device for covering and sealing the filling opening of atank or the like of the type provided with inclined planes on the tankadjacent to the opening and a sealing gasket at the opening; a sheetmetal spring having opposite fingers engageable with the inclined planesupon rotation of the device to draw the device f resiliently toward theopening to sealingly yieldingly press the gasket thereupon; a head onthe device disposed outwardly of the spring to limit yielding of thespring; and attaching means projected through perforations in the headand then through perforation-s in the spring and secured to the deviceto attach the spring and head to the device.

6. In a cap device for closing the filling opening of a tank or thelike, an attaching part comprising means for attaching it to the tank; acovering part coupled to the attaching part to rotate freely -on an axisof rotation; a key operable lock mechanism to lock the two par-tstogether and comprising a series of radially inwardly extending teethwith recesses therebetween on one part arranged about said axis, atongue loosely guided on the other part to reciprocate generallyradially thereon toward and from the teeth and recesses, means operatedby a key to reciprocate the reciprocator andto lmove jmutually engagedportions being vrelatively formed so as-to 'deflect the-tongue in thegeneral 1 :direction of said axis, and spring means reacting on thedeflected tongue to restore it and cause it to move into a recess uponsubsequent relative rotation of the attaching and covering parts.

7. In a cap device for closing the lling opening of a tank or the like,an attaching part comprising means for attaching it to the tank; -a

covering part freely rotatably coupled to the attaching part; a keyoperable lock mechanism to lock the two parts together and comprising areciprocator movably supported by one part but unattached thereto and aplurality of teeth on the other part with tooth spaces therebetween; anupwardly inclined face on each tooth; means responsive to movement of akey to reciprocate the reciprocator to cause it to ride up on a toothface aligned therewith; a spring reacting on the reciprocator to hold itagainst rattling under vibration and to yieldably engage it with thetooth face; the reciprocator being rotatably movable with the saidcovering part to move it from the inclined face to the yadjacent toothspace; and the spring snapping it into said space.

8. In a cap device for closing the filling opening of a tank or thelike, an attaching part comprising means for attaching it to the tankand a covering part having a peripheral skirt portion surrounding andcovering the attaching part; means freely rotatably coupling the partstogether; a lock mechanism operable by a key to lock the two partstogether against rotation; the coupling means comprising mutuallyengageable annular shoulders on the two parts respectively to centerthem for relative rotation, an outwardly laterally extending annularflange on one part, an annular ring having a portion -overlapping theflange, and an annular fin on the other part deformable by axiallydirected force to cause it to overlap the ring, said coupling meansbeing disposed inwardly of and adjacent to the base of the said skirtportion.

9. In a device for closing the filling opening of a tank or the like, anattaching part comprising means for attaching it to the tank anda-covering part freely rotatably coupled to the attaching part; a lockmechanism operable by a key to lock the two parts together when the keyis inserted manually in the lock mechanism and then rotated in onedirection, and to unlock them when rotated in the other direction; meansto prevent removal of the key except when the two parts are unlockedfrom each other, and spring means acting to eject the key upon turningit manually to unlocking position.

10. In a device for closing a lling opening of a tank or the like, anattaching part comprising means for attaching it to the tank and acovering part therefor; a locking mechanism operable by a key to lockthe two parts together comprising an element rotatable on an axis byrotation of the key; and means to prevent removal of the key except whenthe two parts are unlocked from each other comprising a perforation inthe key and a tongue on the covering part disposed to enter theperforation when the key rotates the rotatable element to the lockingposition.

11. In a cap device for closing the lling opening of a tank or the like,an attaching part comprising means for attaching it to lthe tank and acovering part freely rotatably coupled to the attaching part; alockrmechanism operable by a key to lock the two parts together againstrotarelative rotation, an outwardlylaterally extending flange on onepart, a ring having portions overlapping the flange, anda 1in on theother part deformable by axially 'directed force to tion; the couplingmeans comprising mutually 5 cause it to overlap the ring.-

engageable annularly disposed shoulder portions on the two partsrespectively to center them for y l SOLOMON WISE.

